Cricket floods the Net
Cybersurfing with Amar Chandel
WITH the World Cup touching upon the life of all of us in one way or the other, it was but natural that websites connected with cricket would mushroom on the Internet. There are so many now that it is hard to make one’s choice. To the credit of the hosts, it must be said that most of them are well made and well tended by way of updating etc.

• New products & discoveries
• Science Quiz

Fuel cell cars are coming
by Shirish Joshi

TOYOTA and General Motors, two well-known names in automobile industry, in the whole world have reached a five-year agreement to jointly develop cars and trucks that can run on fuel cells and other environmentally friendly alternative-fuel technology. Pooling their efforts should result in commercially viable advanced technologies faster and at a lower cost to customers.

The new venture will involve research and development of electric, hybrid electric and fuelcell technology. Hybrid electric vehicles typically combine an electric motor with other power systems.

Fuel cells produce electricity using a chemical reaction between hydrogen and oxygen and produce little or no emissions. The technology was developed for use in spacecraft, but problems in supplying and storing hydrogen have hampered plans to use it for cars. So far, fuel cells remain prohibitively expensive.

The electric car has failed to catch on in the markets where it is being released. Toyota brought the first hybrid electric car to market, the Prius, in Japan two years ago. The Prius uses petrol and electricity and is scheduled to go on sale in the USA and Europe very soon.

A fuel cell liberates electrons from hydrogen molecules to produce electricity. The hydrogen then meets up with oxygen in the air to form water.

Greenhouse gases, the related global warming and increasingly poor urban air quality have made automotive emissions a “hot” topic, and one of the solutions getting the most attention is fuel cells.

Essentially fuel cell cars are electric cars. They just create their electricity chemically instead of storing it in a battery. A fuel cell mixes two different materials, often hydrogen though sometimes natural gas or methyl alcohol and oxygen, to produce electricity and water. The idea appears extremely simple but the storage process presents serious problems.

Hydrogen is a gas at normal temperatures and pressures. Gases take up a lot of room compared to liquids for a given weight. To store the large quantities needed to power a car requires that the hydrogen be pressurised in tanks that often resemble smaller but stronger version of the ones we use at homes.

In addition, hydrogen is highly inflammable The Chamber where the tanks are stored requires special ventilation to keep hazardous fumes from gathering should anything happen to the tanks or their nozzles.

The next challenge is combining the hydrogen and oxygen in the air in just the right way. To generate electricity, the hydrogen and oxygen are individually introduced to electrodes. As the hydrogen passes over the electrode, it loses an electron leaving a positively charged hydrogenion or proton. The electron moves through a conducting material to produce electricity while the hydrogen proton combines with oxygen in the air to form water.

There are two distinct advantages of fuel cells that warrant their development compared to battery technologies. The first is that the byproducts are harmless. Batteries are typically charged by electricity generated by big power stations often run by fossil fuels. Second, the hydrogen tanks are much easier to refill than a battery is to recharge. The hydrogen tanks could be replenished in way similar to a gas tank. Batteries take much longer — potentially several hours — to recharge fully.

But the technology itself is still very immature, Automobile engineers have been working on technology to convert petrol to hydrogen on board the car, eliminating the need for a heavy, expensive hydrogen storage tank and a system of hydrogen filling stations.

While methanol or methyl alcohol is not widely available now, it could be distributed through the existing network of filling stations. It is easier to convert into hydrogen and produces less emissions.

However, the scientists are not abandoning the research to reform gasoline into hydrogen, but in will take a back seat now. A fuel-cell vehicle would get 50 per cent better fuel economy than the same vehicle with a conventional petrol driven engine, once the weight of the fuelconversion equipment is reduced. That means today’s typical car running 6 to 8 km/lit would instead get 10 to 12 km/it and its range would increase to about 1000 km from 600 km.

Another problem is the time it takes to warm up a fuel cell stack: up to 30 minutes with existing technology. This is clearly unacceptable. If they can get the start-up time down to one minute, and then you would only need a small battery to get you started and the overall vehicle concept may make sense.

Much more research work also is needed to reduce the cost of a fuel-cell power system. Even the most advanced systems, using stored hydrogen, are about 10 times too costly to be commercially viable.

The biggest potential benefit of fuel cells is in lower emissions. Engineers expect that fuel-cell technology could produce a vehicle with 10 times fewer emissions than the average vehicle today.

The simple principles of extracting electricity from a fuel cell were discovered more than 150 years ago. It is widely known that a jolt of electricity can separate water into its component hydrogen and oxygen molecules. In 1839, William Grove, a physicist turned judge, discovered that the reverse was also true. Hydrogen atoms could be induced to give up their electrons to a metal electrode, called the anode. The positively charged hydrogen ions left behind would swim to another electrode, the cathode, through either a liquid or a membrane.

The electrons also travelled to the cathode, but through an external circuit, which could provide power to an attached engine. At the cathode, the electrons then combined with the hydrogen ions and oxygen to produce water.

This simple reaction, however, is extraordinarily difficult to produce in practice. Hydrogen atoms must be induced to give up their electrons using catalysts.

In the real world, “difficult” translates to expensive. That’s why fuel cells were first used as late as the 1960s in spacecraft, which needed clean, reliable power (and water). Each kilowatt of fuel cell energy for the space programme the cost up to half a million dollars to produce.

Scientist have been able to slash that figure a thousandfold, to about $ 500 per kilowatt of power for an automobile. They made a fuel cell called the Proton Exchange Membrane cell (PEM). The PEM’s cathode and anode are separated by a thin polymer membrane that allows only the hydrogen ions to pass through.

The results have led to a mini rush among car manufacturers to fuel cell engines. Now they have begun the race to lower the cost to the level of today’s internal combustion engine. Cost remains the biggest hurdle to widespread adoption of fuel cells in cars.

The researchers are confident that they can reach this goal with a combination of better and cheaper materials and refined manufacturing processes. The final objectives they are looking at are higher performance and better reliability, advantages beyond environmental friendly.

Cricket floods the Net
Cybersurfing with Amar Chandel

WITH the World Cup touching upon the life of all of us in one way or the other, it was but natural that websites connected with cricket would mushroom on the Internet. There are so many now that it is hard to make one’s choice. To the credit of the hosts, it must be said that most of them are well made and well tended by way of updating etc.

Still, if one has to pick and choose, my vote would go in for www.cricinfo.org. It not only gives out the latest on the World Cup, but also keeps one posted about various cricketing terms, history, laws, pitches and umpiring. Most important, there is a detailed explanation of the rain rules.

So complicated are these that one needs to master them fully to understand how a team scoring less than the other one can still win in a rain-affected match. While many other sites suffer from access problems, this one has gotten over the difficulty because it has mirror sites in the USA, the UK, India, South Africa and Australia.

On the other had, the strong point of www.icricketer.com is the writeups by well-known personalities like Rameez Raza and Simon Lewis. If one wants to focus on the Indian side, the site to watch is www.khel.com. It gives player profiles in detail and boasts of a comprehensive archive. One found their graphs to be the most interesting.

Among other sites worth a dekho are www.world-cup99.com , www.goworldcup99.com , www.cybercricket.com (which has arranged for live webcasting of the matches) and www.cricmania.com.

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If space research fascinates you as much as it attracts me, the official site of NASA is a permanent treasure trove. Another equally brilliant site one can try is www.spacer.com which too provides authentic information and is updated regularly. It was my source for news items like TecStar wins solar cell contract, Defence Sat stranded, details of the world space transportation summit, how an all-female crew would save money and the electrification of rocket engines. Take your pick.

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To be engaged in making arrangements for the marriage of a daughter or a son is the ultimate in over-work. There are a million things to do and no time for even 10 of them. You are bound to forget one or the other essential tasks. Don’t worry. Help is at hand. A well-built site, www.advol.com , provides details of all that you need to know. There is a budget planner, the responsibilities, ceremonies, traditions, money saving tips and lists of wedding shops online are there. The site caters to western weddings but the idea is so novel and useful that we should have an Indian version soon enough.

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The official website of World Wildlife fund at www.panda.org is always a delight to visit. The layout is thoroughly professional and the photographs are marvellous. There is something for everybody: photogallery, newsroom, The Living Planet section, Just for kids, Art gallery, video library and WWF releases. However the online version of the Living Planet index report takes unusually long to load.

Science Quiz
by J. P. Garg

1. What is the process called by which milk can be preserved for a longer period by alternately heating and cooling it to suitable temperature several times? Who discovered this process?

2. A recent technique to correct blurred vision is to siphon off a part of the cornea of the eye with the help of a laser beam in order to form the image of the object on the retina. What is this technique called?

3. Nitrogen fixation is a very important life-supporting process occurring in nature. Which predominant variety of plants help in the fixation of nitrogen in the soil by bacteria?

4. Which physical quantity is now measured in the units of “siemens”? Why has this unit been so named? Which unit was earlier used for this measurement?

5. Which device is generally used in the thermostat of an iron press, a refrigerator or a geyser to control temperature? How does it keep the temperature constant?

6. What is the general name of the tiny particles suspended in air (having different sizes and chemical composition) that scatter sunlight back into space, thus causing a direct cooling effect? What other function do these particles perform that also causes global cooling, though indirectly?

7. What is “Genymede” and what distinguishes it from others of its class?

8. “No two electrons in an atom can have the same set of four quantum numbers.” What is this principle known as?

9. This common bird does not hatch its eggs but places these in the nest of a koel (cuckoo) for hatching. Which is this bird?

10 “Air is the teacher,, water the father and earth is the mother”. Which Indian scripture contains this verse that glorifies the significance of these natural objects for human existence?

Answers

1. Pasteurization; French chemist Louis Pasteur; 2. Photo refractive keratectomy; 3. Leguminous plants such as beans and peas; 4. Electrical conductance; In honour of German scientist Ernst von Siemens; mho or reciprocal ohm; 5. A bimetallic strip; As the temperature reaches a fixed value, the strip bends due to differential expansion and breaks the circuit; 6. Aerosols; they also act as nuclei for formation of clouds; 7. It is a satellite of planet Jupiter and is the largest satellite in our solar system — even larger than the planet Mercury; 8. Pauli’s exclusion principle; 9. Crow; 10. Japji Sahib (Guru Granth Sahib).

Anti-graffiti coating

Researchers in Germany have developed a special protective film that can be applied on walls of buildings and historical monuments to remove undesired graffiti.

Conventional methods to remove graffit range from organic solvents, paint strippers or high-pressure cleansing equipment to laser treatment. But all this has a negative impact on human beings, the environment and the buildings themselves. There are methods to coat walls in special layers that make cleansing simpler, and some are even paint-repellent.

Researchers of the Fraunhofer institute for Applied Polymer Research in Teltow have developed an anti-graffiti protective layer that can be washed off along with the graffiti itself with a simple jet of water.

A new layer of anti-graffiti protective film is painted onto the wall immediately after cleansing, when the wall is still wet. No damage is done to the undercoator, the facade.

The colour and the outward appearance are not impaired. Micro-organisms cannot enter the facade and harm it as the layer consists of several environment-friendly natural polymers.

A further advantage is that the water does not need to be specially treated and can simply flow off the surface, reports the German newsletter DFD.

Mobile phones make reactions faster

Could your mobile phone make your reactions speedier?

That seems to be the conclusion of the first official study into the effect of mobile phones on humans.

But it’s just another clue in the mystery surrounding the mobile phone.

The study carried out by the British periodical New Scientist poured cold water on widespread fears that mobile phones could cause cancer, but said emissions from mobile phones did appear to have strange effects on living tissue.

These effects could not be reconciled with conventional radiation biology, it added.

Alan Preece, a medical physicist at the University of Bristol, carried out the first study on human responses by clamping a device that mimicked the microwave emissions of analogue or digital mobile phones to the left ear of volunteers.

Switching the device on or off had no effect on their ability to remember words and pictures, but when the headset was switched on, they were quicker at reacting to words flashed on a screen. The change was particularly noticeable with analogue signals, Preece said.

The effect could be due to a slight warming of the brain leading to increased blood flow or change in protein synthesis caused by a reaction of the body’s defence mechanisms, he added.

Hydrogel “stamper” for protein microarray

By using a hydrogel “stamper”, which works in a fashion similar to the action of an ink-stamper on paper, defence scientists in USA have come up with a new technique to produce protein microarrays used in sensing devices.

These would be used in detection and identification of agents of chemical or biological warfare as well as explosives.

The design of these tiny sensors involves forming a surface protein layer by photolithographic or inkjet printing technology. It helps give the protein a micro-pattern which interacts with molecules to be detected.

The scientists from USA’s Naval Research Laboratory have adopted a new approach to produce biomolecular patterns with the creation of a new gel-based ‘microstamper’ that delivers a protein film directly onto a surface in a single step, according to a report in the journal Chemtech.

The stamper is composed of a micromoulded, elastic hydrogel that is loaded with a solution of protein (or another biomolecule). When brought briefly into contact with a receiving surface, the stamper deposits a protein film in a manner analogous to the action of an ink stamper on paper.

Protection against UV light

German researchers have discovered polymers that make ultraviolet (UV) light visible.

Although the human eye cannot recongnise UV light, the effects of its high-energy rays are clearly perceptible.

For example, they can cause sunburn and even skin cancer. Scientists have, therefore, make several attempts to find a simple method that would enable anyone to measure UV radiation, for example on the beach.

Special plastics developed by researchers at the Fraunhofer Institute for Applied Polymer Research in Teltow are one such option, reports the German newsletter DFD.

The researchers have fitted certain groups of molecules into the polymers that absorb shortwave UV light and then radiate blue light.